Sheet material conveying device

Abstract

To enable early transition to a sleep state on the basis of conditions for returning from sleep and a state after returning, and reduce power consumption without lowering convenience.SOLUTION: In an image reading device A, a control unit comprises: a mode control unit 203 that switches and controls between a first mode and a second mode having lower power consumption than the first mode; a second mode switching time setting unit 204 that sets a switching time until switching from the first mode to the second mode; a first mode switching instruction means group 201 including a plurality of pieces of first mode switching instruction means for instructing switching from the second mode to the first mode; and a first mode switching instruction means detection unit 206 that detects which of the first mode switching instruction means in the first mode switching instruction means group 201 has instructed the switching to the first mode. The second mode switching time setting unit 204 changes the switching time according to a detection result of the first mode switching instruction means detection unit 206.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a transition time to a power saving state of a sheet material transport device. [Background technology]

[0002] 2. Description of the Related Art Some sheet material conveying devices, such as image reading devices, are equipped with an original detection sensor for detecting whether an original has been placed on the device.

[0003] In addition, it is desirable for the sheet material transport device to quickly transition to a normal state when a sheet material is placed on the platen, and to reduce power consumption.

[0004] Lever-type optical sensors that detect when a document has been fed can sometimes detect it incorrectly due to chattering that occurs when a document is placed on or removed from the feed tray, or due to shaking of the device. In devices that switch between sleep and standby modes based on the sensor's detection results, false detections can cause the device to switch from sleep to standby, resulting in unnecessary power consumption.

[0005] In response to this, Patent Document 1 discloses a technique for removing chattering when detecting an original and confirming whether the paper has actually been fed. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5348119 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when a user places a document on the document tray, the device remains in a power-saving state and continues to detect the document for a predetermined period of time to prevent false detection of the document. Therefore, since the power-saving state is maintained even after the user places a document, it takes some time for the device to transition to normal mode. [Means for solving the problem]

[0008] In view of the above problems, a sheet material conveying device according to the present invention is a mode control unit that switches between a first mode and a second mode that consumes less power than the first mode; a second mode switching time setting unit that sets a switching time required to switch from the first mode to the second mode; a first mode switching instruction means group consisting of a plurality of first mode switching instruction means for instructing switching from the second mode to the first mode; a first mode switching instruction means detection unit for detecting which first mode switching instruction means from the group of first mode switching instruction means has instructed switching to the first mode; Equipped with The second mode switching time setting unit changes the switching time in accordance with the detection result of the first mode switching instruction means detection unit. [Effects of the Invention]

[0009] According to the present invention, it is possible to transition to a sleep state early based on the conditions for returning from sleep and the state after returning, thereby reducing power consumption without reducing convenience. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a front view of a sheet material conveying device according to a first embodiment of the present invention; [Figure 2] 1 is a side cross-sectional view of a sheet material conveying device according to a first embodiment of the present invention; [Figure 3] Schematic cross-sectional view of the document detection structure (when no document is present) [Figure 4] Schematic cross-sectional view of the document detection structure (with document present) [Figure 5] Circuit Block Diagram [Figure 6] An example of the configuration of the document detection unit [Figure 7] Flowchart of the sheet material conveying device according to the first embodiment [Figure 8] 10 is a display example when an instruction to change the time until transition to the sleep state is given in the first embodiment. [Figure 9] 1 is a table showing an example of a combination of conditions for determining the time until transition to a sleep state in the first embodiment. [Figure 10] 10 is a flowchart of a control process for a document detection sensor of a sheet material conveying device according to a first embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0011] FIG. 1 is a front view of a sheet material conveying device according to a first embodiment of the present invention. More precisely, it is a view from a direction perpendicular to the front panel 80, which is inclined on the front side of the image reading device A, and is a view from slightly above the front when the device is placed.

[0012] The upper unit 103 is an upper unit that forms a conveying path of the sheet material conveying device. The upper unit 103 is provided with a front panel 80.

[0013] A display panel 85 is provided on the front panel 80, and an input unit 83 is provided inside the display panel 85. The input unit 83 is used to input instructions regarding the operation of the sheet material conveying device A, and is provided with a start key, a stop key, etc. for starting the sheet material conveying operation, and a display unit 84 is provided adjacent to the input unit 83.

[0014] A discharge opening 103a is provided at the bottom of the upper unit 103, and the sheet S placed on the table 1 is discharged onto the discharge tray 2 through the discharge opening 103a.

[0015] FIG. 2 is a cross-sectional side view of the sheet material conveying device according to the first embodiment of the present invention.

[0016] <Device configuration> The image reading device A is a device that conveys one or more sheets S stacked on a table 1 into the device one by one along a path RT, reads the images thereon, and discharges the sheets onto a discharge tray 2.

[0017] The sheet S to be read is, for example, an office paper, a check, a cheque, a card, etc., and may be a thick or thin sheet. Examples of cards include an insurance card, a driver's license, a credit card, etc.

[0018] Sheets S also include booklets such as passports. When a booklet is the target, the booklet is placed in a transparent holder in a double-page spread state and placed on the table 1, whereby the booklet is transported together with the holder and its image can be read.

[0019] <Paper Feed> A first conveying unit 10 is provided as a feeding mechanism that feeds the sheet S along the path RT. In this embodiment, the first conveying unit 10 includes a feed roller 11 and a separation roller 12 arranged opposite the feed roller 11, and sequentially conveys the sheets S on the mounting table 1 one by one in a conveying direction D1. A driving force is transmitted to the feed roller 11 from a paper feed drive unit 3 such as a motor via a transmission unit 5, and the feed roller 11 is driven to rotate in the direction of the arrow in the figure (the forward direction for conveying the sheet S along the path RT). The transmission unit 5 is, for example, an electromagnetic clutch, and connects and disconnects the driving force from the paper feed drive unit 3 to the feed roller 11.

[0020] <Drive unit> In this embodiment, for example, the transmission unit 5 that connects the paper feed drive unit 3 and the feed roller 11 is in a state in which a driving force is normally transmitted, and the driving force is cut off when the sheet S is fed backward. When the transmission of the driving force is cut off by the transmission unit 5, the feed roller 11 is in a state in which it can rotate freely. Note that such a transmission unit 5 does not need to be provided when the feed roller 11 is driven in only one direction.

[0021] <Separated structure> The separation roller 12, which is disposed opposite the feed roller 11, is a roller for separating the sheets S one by one, and is pressed against the feed roller 11 with a constant pressure. To ensure this pressed state, the separation roller 12 is configured to be swingable and to be biased toward the feed roller 11. A driving force is transmitted to the separation roller 12 from the paper feed drive unit 3 via a torque limiter 12a, and the separation roller 12 is driven to rotate in the direction of the solid arrow (the opposite direction to the forward direction of the feed roller 11).

[0022] Since the transmission of driving force to the separation roller 12 is restricted by the torque limiter 12a, when the separation roller 12 is in contact with the feed roller 11, it rotates in a direction (indicated by the dashed arrow) that rotates together with the feed roller 11. As a result, when multiple sheets S are conveyed to the pressure contact portion between the feed roller 11 and the separation roller 12, two or more sheets S except one are blocked so that they cannot be conveyed downstream.

[0023] In this embodiment, the separation mechanism is configured by the separation roller 12 and the feed roller 11, but such a separation mechanism is not necessarily provided, and any feeding mechanism that sequentially feeds the sheets S one by one to the path RT will suffice. Furthermore, in the case where a separation mechanism is provided, instead of a configuration such as the separation roller 121, a separation pad that applies friction to the sheets S may be pressed against the feed roller 11 to perform a similar separation operation.

[0024] <Transport mechanism> The second conveying section 20, which serves as a conveying mechanism located downstream of the first conveying section 10 in the conveying direction, includes a drive roller 21 and a driven roller 22 driven by the drive roller 21, and conveys the sheet S conveyed from the first conveying section 10 downstream. A driving force is transmitted to the drive roller 21 from a conveying drive section 4 such as a motor, and the drive roller 21 is driven to rotate in the direction of the arrow in the figure. The driven roller 22 is pressed against the drive roller 21 with a constant pressure, and rotates along with the drive roller 21. The driven roller 22 may be configured to be biased against the drive roller 21 by a biasing unit (not shown) such as a spring.

[0025] The third conveying section 30, which is located downstream in the conveying direction from the second conveying section 30, includes a drive roller 31 and a driven roller 32 that communicates with the drive roller 31, and conveys the sheet S conveyed from the second conveying section 20 to the discharge tray 2. In other words, the third conveying section 30 functions as a discharge mechanism. A driving force is transmitted to the drive roller 31 from a conveying drive section 4 such as a motor, and the drive roller 32 is driven to rotate in the direction of the arrow in the figure. The driven roller 32 is pressed against the drive roller 31 with a constant pressure, and rotates along with the drive roller 31. The driven roller 32 may be configured to be biased against the drive roller 31 by a biasing unit (not shown) such as a spring.

[0026] <Image reading structure> Between the second conveying section 20 and the third conveying section 30, image reading sensors 70 are arranged, one on each side of the path RT. The image reading sensors 70 optically scan, convert into electrical signals, and read as image data, and are equipped with a light source such as an LED, an image sensor, a lens array, etc. In this embodiment, one image reading sensor 70 is arranged on each side of the path RT to read the front and back sides of the sheet S, but it is also possible to arrange one image reading sensor 70 on only one side of the path RT and configure it to read only one side of the sheet S. Furthermore, in this embodiment, the image reading sensors 70 are arranged on both sides of the route RT so as to face each other, but for example, they may be arranged at intervals in the direction of the route RT.

[0027] <Document detection structure> A transmissive photointerrupter 81 and a document detection lever 82 are arranged upstream of the first transport section. The document detection lever 82 interrupts the optical path of the transmissive photointerrupter 81, thereby determining whether a document is present. In this embodiment, a reflective sensor is used to detect whether a document has been placed on the document table 1. In this embodiment, the structure is such that the transmission type photointerrupter 81 and the document detection lever 82 are arranged, but for example, an ultrasonic wave transmitter and receiver may be arranged.

[0028] <Document detection structure> FIG. 3 is a schematic cross-sectional view of the document detection structure (when no document is present), and FIG. 4 is a schematic cross-sectional view of the document detection structure (when a document is present). To detect the presence or absence of a document on the document table 1, a document detection unit 90 is provided above the paper feed roller 11. The document detection unit 90 is a lever-type sensor. When a document is set on the document table so that the leading edge of the document abuts against the claw portion 15a of the document stopper 15, the leading edge of the document pushes against the lever portion 90a, thereby detecting the presence of a document, as described below. Note that in this embodiment, document detection is performed using a lever, but document detection may also be performed using, for example, a transmission-type optical sensor.

[0029] <Block diagram of image reader> FIG. 5 is a block diagram showing electrical connections according to the first embodiment of the present invention. The image reading device A is equipped with the aforementioned paper feed drive unit 3, conveying drive unit 4, transmission unit 5, power distribution control unit 6, double feed detection sensor 40, image reading sensor 70, image reading position sensor 50, document detection unit 90, input unit 83, and display unit 84.

[0030] The document detection unit 90 and the input unit 83 constitute a first mode switching instruction means group 201, which detects that the user is operating the sheet material conveying device and sends a signal to the first mode switching instruction means detection unit.

[0031] Although the document detection unit 90 and the input unit 83 are given as examples of the first mode switching instruction means group 201, the first mode switching instruction means group is not limited thereto. As another example, a signal from an external device may be used as the first mode switching instruction means group.

[0032] In addition, a power distribution control unit 6 is provided to supply power to each drive unit and sensor within the device. The power distribution control unit 6 is composed of a FET and the like. It receives a signal from an I / O unit 207 and controls the power by driving the FET. In this embodiment, power distribution control is performed using FETs, but power distribution control using photocouplers, for example, may also be used.

[0033] In addition to the above, a USB terminal 108, a DC power terminal 109, a voltage conversion circuit 281, and a power switch circuit 282 are also mounted.

[0034] The control unit 200 is composed of a CPU, a microcomputer, etc., and is responsible for overall control of the device, calculations, and information transfer. Controls performed by the control unit 200 include image reading control (transmission unit 5), etc. The control unit 200 also includes a communication unit 202, a mode control unit 203, a second mode switching time setting unit 204, a memory unit 205, a first mode switching instruction means detection unit 206, and an I / O unit 207.

[0035] The communication unit 202 communicates information via a wired connection with an external device 285. Examples of communication standards include USB, LAN, and SCSI.

[0036] The mode control unit 203 switches between the first mode and the second mode, which consumes less power than the first mode, to perform control.

[0037] The second mode switching time setting unit 204 sets the time required to switch from the first mode to the second mode.

[0038] The storage unit 205 stores the setting of the time until switching from the first mode to the second mode.

[0039] The first mode switching instruction means detection unit 206 detects a signal to switch to the first mode.

[0040] The I / O unit 207 detects input signals and controls the output described above. The signals to be input and detected include button inputs from the input unit 83, the output voltage of the image reading sensor 70, the output voltage of the document detection unit 90, and the like.

[0041] The DC power supply device 283 supplies the device with a DC voltage required to drive the image reading device A. The DC power supply device 283 includes an AC adapter that converts commercial power into DC voltage, an external battery, a mobile battery, and the like.

[0042] In this embodiment, the DC power supply device 283 is connected to the image reading device A from the outside, but it is also possible to supply commercial power to the image reading device and have an AC / DC conversion power supply unit built into the image reading device A that converts it to DC voltage inside the device.

[0043] The DC power supply terminal 109 is a connection terminal for connecting a power supply line for supplying power from the DC power supply device 283 to the image reading device A.

[0044] The power supply SW circuit 282 is an on / off switch for switching whether or not the DC voltage supplied from the DC power supply device 283 is supplied to the device. When the power supply SW circuit 282 is turned on, power is supplied to the voltage conversion circuit 281, the paper feed drive unit 3, the transport drive unit 4, the transmission unit 5, and the double feed detection sensor 40.

[0045] When the power supply SW circuit 282 is turned on, the voltage conversion circuit 281 converts the supplied power into the voltage required to drive the image reading sensor 70, the image reading position sensor 50, the document detection unit 90, the input unit 83, and the control unit 200.

[0046] The USB terminal 108 is a connection terminal for an interface for transmitting and receiving data such as image information between an external device 285 and a communication unit 202 in the image reading device A. The image reading device A and the external device 285 are connected via a USB cable 284.

[0047] The USB cable 284 is a cable for connecting devices together, and in this embodiment, the devices are connected together by inserting the USB cable 284 into the USB terminals of the image reading device A and the external device 285, respectively.

[0048] The external device 285 is a device that performs complex calculations such as numerical calculations, information processing, and data processing at high speed and in large quantities, and is a terminal such as a personal computer or tablet.

[0049] <Basic operations for image reading> The following describes the basic operation of the image reading device A. When the control unit 200 receives an instruction to start image reading from an external device, it starts driving the first conveying unit 10 to the third conveying unit 30. The sheets S placed on the mounting table 1 are conveyed one by one, starting with the bottommost sheet S.

[0050] In addition, in order to perform image reading by the image reading sensor 70, the second conveying section 20 and the third conveying section 30 convey the sheet S at a low speed.In addition, in order to reliably prevent the subsequent sheet S from catching up with the preceding sheet S, the conveying speed is controlled to always be equal to or greater than the conveying speed of the first conveying section 10.

[0051] Furthermore, even if the conveying speed of the sheet S by the second control unit 20 and the third conveying unit 30 and the conveying speed of the sheet S by the first conveying unit 10 are the same, it is also possible to form a minimum gap between the preceding sheet S and the succeeding sheet S by controlling the paper feed drive unit 3 to intermittently shift the timing at which the feeding of the succeeding sheet S begins.

[0052] When the leading edge of the sheet S reaches the image reading position sensor 50 or 60, a detection signal is output from the image reading position sensor 50 or 60, and the control unit 200 determines the reading timing and starts reading the image by the image reading sensor 70.

[0053] The image data read by the image reading sensor 70 is transmitted by the control unit 200 to, for example, the external device 285 that issued the image reading instruction.

[0054] An example of the configuration of the document detection unit 90 will be described using FIG. 6. FIG. 4 is a schematic cross-sectional view of the document detection structure (with a document present). To detect the presence or absence of a document on the document table 1, a document detection sensor 90 is provided above the paper feed roller 11. The document detection sensor 90 is a lever-type sensor. When a document is placed on the document table so that its leading edge abuts against the tab 15a of the document stopper 15, the leading edge of the document pushes the lever 90a. When the lever 90a is pushed and rotated, the optical paths of the light-emitting element 91 and the light-receiving element 92 change. The change in the optical path changes the output of the light-receiving element, and the presence of a document is detected. The light-emitting period T1, light-emitting non-period I1 (I1a, I1b), and light-receiving timing I2 (I2a, I2b) of the light-emitting element 91 are as shown in FIG. 10. As will be described later, the light-emitting non-period I1 and light-receiving timing I2 change depending on the state of the image reading device A.

[0055] <Operation flow> The operation flow of the image reading device A according to the first embodiment of the present invention will be described with reference to FIG.

[0056] When a predetermined condition is met (for example, after a predetermined time has elapsed), the device transitions from the standby state to a sleep state, which consumes less power (S201).

[0057] The document detection unit 90 operates at a detection interval I2b, which is wider than the detection interval I2a in the standby state, and when the document detection unit 90 detects a document (Yes in S202), it sets the time until transition to the sleep state to the sleep transition time Ta (S203) and then transitions to the standby state (S208).

[0058] The first mode switching instruction means detection unit 206 receives the result of document detection by the document detection unit 90, and if the document detection sensor does not detect a document (No in S202), it checks whether the input unit 83 has been operated (S204). If the first mode switching instruction means detection unit 206 detects that the input unit has been operated (Yes in S204), it sets the time until transition to the sleep state to a sleep transition time Tb (S205), and transitions to the standby state (S208).

[0059] If the first mode switching instruction means detection unit 206 has not detected any operation on the input unit (No in S204), it checks whether or not an instruction to cancel the sleep state has been issued (S206). If it determines that an instruction to enter the sleep state has been issued (Yes in S206), it sets the time until the transition to the sleep state as the sleep transition time T (S207), and transitions to the standby state (S208).

[0060] After transitioning to the standby state, it is checked whether there is an instruction to change the time until transitioning to the sleep state (S209). If a set time change instruction to change the time until transitioning to the sleep state has been given (Yes in S209), the time T until transitioning to the sleep state is reset (S212). Note that here, the set time change instruction is considered to be any operation on the input unit in the standby state. At that time, the sleep transition time T is configured to be set. However, this is not limited to this, and it may also be determined that there has been an instruction to change the set time when some other operation has been performed.

[0061] If there is no instruction to change the set time until the transition to the sleep state (No in S209), it is checked whether the document detection sensor detects a document (S210).

[0062] If the document detection sensor detects a document (Yes in S210), it is checked whether an instruction to read an image has been issued (S211).

[0063] If the document detection sensor does not detect a document (No in S210), the timer Tx starts counting until the device transitions to the sleep state (S214).

[0064] On the other hand, if an instruction to change the set time is given in S209, the sleep transition time T is set to the time until transition to the sleep state (S217), and the process proceeds to S214.

[0065] Also, if there is no instruction to start image reading in S211, the process proceeds to S217.

[0066] When the timer Tx starts counting, it counts the elapsed time and determines whether the sleep transition time (T, Ta, Tb) has elapsed (S215).

[0067] If the sleep transition time and the elapsed time count (timer Tx) match (Yes in S215), the process transitions to S201 and the device transitions to the sleep state.

[0068] If the sleep transition time and the elapsed time count (timer Tx) do not match (Yes in S215), the process transitions to S208 and maintains the standby state. Note that the process waits for the sleep transition time to elapse while counting timer Tx thereafter, but if timer Tx has already started counting when the process transitions to S214, nothing is done in S214.

[0069] If an instruction to start image reading is given in S211 (Yes in S211), the system transitions to an image reading state (S213). That is, in this state, the first conveying section 10 and the like are driven to convey the sheet S while the image reading unit 70 starts reading the image, and the system transitions to S216. If the image reading process for all sheets is completed (Yes in S216), the system transitions to a standby state (S208). If the image reading process for all sheets is not completed (No in S216), the system continues to remain in the image reading state (S216).

[0070] In this embodiment, an image reading device is used as an example, but the device may also be a sheet conveying device that does not read images but only conveys sheet material, or a device that performs other operations and processes on the conveyed sheets, and is not limited to image reading.

[0071] 8 shows an example of a display in this embodiment in which the user can specify the sleep transition time as desired. By allowing the user to specify the time on this display screen, the user can set the time as desired until the device transitions to the sleep state.

[0072] The display example in FIG. 8 is an example, and is not intended to limit the display, and the display unit is not limited to only the display on the display unit 84 of the sheet material conveying device A.

[0073] 9 shows a combination of conditions for determining the time until transition to the sleep state in this embodiment. As described above, the sleep transition time changes depending on the cause of waking up from the sleep state and the state of the subsequent standby. Note that the example shown in FIG. 9 is not intended to limit the sleep termination cause, standby state, or sleep transition time.

[0074] FIG. 10 shows a timing chart of the control process in the document detection unit 90 in this embodiment. The light emission cycle and light reception timing are changed depending on the state of the sheet material conveying device A. That is, the light emission period T1 of the light-emitting element 91 is always the same period required for detection, but a light emission stop period I1a is set in the standby state, and a light emission stop period I1b is set in the sleep state. The light reception timing of the light-receiving element 92 is also changed accordingly. A light reception timing I2a is set in the standby state, and a light reception timing I2b is set in the sleep state. In either case, the light reception timing is set to coincide with the end of the light emission period T1 of the light-emitting element 91. By setting I1b > I1a, the frequency of light emission in the sleep state is reduced compared to the standby state, thereby reducing power consumption in the sleep state. Note that FIG. 10 is merely an example, and is not intended to limit the number and cycles of light emission and light reception, or the sensors used for control. [Explanation of symbols]

[0075] A Image reader S sheet material 1. Mounting table 83 Input section 84 Display section 85 Display Panel 90 Document detection unit 200 control section

Claims

1. a mode control unit that switches between a first mode and a second mode that consumes less power than the first mode; a second mode switching time setting unit that sets a switching time required to switch from the first mode to the second mode; a first mode switching instruction means group consisting of a plurality of first mode switching instruction means for instructing switching from the second mode to the first mode; a first mode switching instruction means detection unit for detecting which first mode switching instruction means among the group of first mode switching instruction means has instructed switching to the first mode; Equipped with The sheet conveying device according to claim 1, wherein the second mode switching time setting unit changes the switching time in accordance with a detection result of the first mode switching instruction means detection unit.

2. The document reader includes a document table on which a document can be placed, and a document detection unit that detects that a document has been placed on the document table, 2. The sheet material conveying device according to claim 1, wherein the document detecting section is the first mode switching instruction section.

3. an input unit for inputting instructions regarding the operation of the sheet material conveying device; the input unit is the first mode switching instruction means, The sheet material conveying device according to claim 2, characterized in that the second mode switching time setting unit sets the switching time when the first mode is switched to by operating the input unit as the switching instruction to be longer than the switching time when the first mode is switched to by placing a document on the document detection unit as the switching instruction.

4. an input unit for inputting the switching time; a display unit that displays a display screen on which the set time input by the input unit can be set as the switching time; 2. The sheet material transport device according to claim 1, further comprising:

Images